#include <stdio.h>
void Fun()
{
	for (char killer = 'a'; killer < 'd'; killer++)
	{
		if ((killer != 'a')+( killer == 'c')  + (killer == 'd')+(  killer != 'd') == 3)
		{
			printf("killer  :%c ", killer);
		}
	}
}

int main()
{
	Fun();
	return 0;
}